Move Creation Workshop

[Handsome Jack]

I don't think he'd need to specify "bullet speed" in this case. Because it only needs to move as quickly as necessary to block a projectile. If I made a Bracers of Bullet Deflection Move, I wouldn't need to say "and these can be placed in the path of the bullet at bullet speed." It's assumed it moves quickly enough to serve the purpose it was purchased for. Use common sense. Mechanically, tossing a rock is no different from blocking it with a shield. Its personal flavour.